In Numbers, chapter twelve, verse one, Mariam and Aaron speak against Moses due to the woman he married: she was an Ethiopian. Moses’ marriage to an Ethiopian woman was not legally or morally wrong. Mariam and Aaron’s complaint was a charade to cover their jealousy of Moses’ authority. These two were both relatives of Moses. Why would Aaron, Moses’ brother-in-law, succumb to joining Mariam with this behavior?
Miriam is first responsible for the transgression and so only punished. Aaron was drawn into the sin by her and acknowledged his fault and forgiven: it must be a great trial to Moses, not only to be spoken against by the people, as he often was, but by his near relations and these gracious persons, and concerned with him in leading and guiding the people through the wilderness. Aaron did not plan this conflict, but Mariam did. Jealousy can lead to a sinful path, especially when it involves a servant of God who is humble and did nothing but good to the person complaining. The accuser does not realize God is there and will protect His servant, and they are not because they allow sin to creep in and eventually lead to doom.
David experienced similar behavior from Saul. When both were in battle against the Philistines, the women came out of Israel dancing and singing that Saul was slaying thousands while David tens of thousands. The anger that sparked jealousy from that episode led to the ruin of Saul. Another situation is Cain and Abel. The offering that was given to the Lord by Abel caused Cain to slay him in the field. These examples generated a sinful submission from the heart and expressed physically. In most cases, God is there to intervene on our behalf. Unfortunately, in the Abel-Cain incident, Abel did not survive the sinful act of his brother.
Today, there are many situations like Moses and his relatives. Some problem arises that is not significant only to find out the truth behind the charade: jealousy.